• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (c) 2001-2003 The FFmpeg project
3  *
4  * first version by Francois Revol (revol@free.fr)
5  * fringe ADPCM codecs (e.g., DK3, DK4, Westwood)
6  *   by Mike Melanson (melanson@pcisys.net)
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #include "avcodec.h"
26 #include "put_bits.h"
27 #include "bytestream.h"
28 #include "adpcm.h"
29 #include "adpcm_data.h"
30 #include "internal.h"
31 
32 /**
33  * @file
34  * ADPCM encoders
35  * See ADPCM decoder reference documents for codec information.
36  */
37 
38 typedef struct TrellisPath {
39     int nibble;
40     int prev;
41 } TrellisPath;
42 
43 typedef struct TrellisNode {
44     uint32_t ssd;
45     int path;
46     int sample1;
47     int sample2;
48     int step;
49 } TrellisNode;
50 
51 typedef struct ADPCMEncodeContext {
52     ADPCMChannelStatus status[6];
53     TrellisPath *paths;
54     TrellisNode *node_buf;
55     TrellisNode **nodep_buf;
56     uint8_t *trellis_hash;
57 } ADPCMEncodeContext;
58 
59 #define FREEZE_INTERVAL 128
60 
61 static av_cold int adpcm_encode_close(AVCodecContext *avctx);
62 
adpcm_encode_init(AVCodecContext * avctx)63 static av_cold int adpcm_encode_init(AVCodecContext *avctx)
64 {
65     ADPCMEncodeContext *s = avctx->priv_data;
66     uint8_t *extradata;
67     int i;
68     int ret = AVERROR(ENOMEM);
69 
70     if (avctx->channels > 2) {
71         av_log(avctx, AV_LOG_ERROR, "only stereo or mono is supported\n");
72         return AVERROR(EINVAL);
73     }
74 
75     if (avctx->trellis && (unsigned)avctx->trellis > 16U) {
76         av_log(avctx, AV_LOG_ERROR, "invalid trellis size\n");
77         return AVERROR(EINVAL);
78     }
79 
80     if (avctx->trellis && avctx->codec->id == AV_CODEC_ID_ADPCM_IMA_SSI) {
81         /*
82          * The current trellis implementation doesn't work for extended
83          * runs of samples without periodic resets. Disallow it.
84          */
85         av_log(avctx, AV_LOG_ERROR, "trellis not supported\n");
86         return AVERROR_PATCHWELCOME;
87     }
88 
89     if (avctx->trellis) {
90         int frontier  = 1 << avctx->trellis;
91         int max_paths =  frontier * FREEZE_INTERVAL;
92         FF_ALLOC_OR_GOTO(avctx, s->paths,
93                          max_paths * sizeof(*s->paths), error);
94         FF_ALLOC_OR_GOTO(avctx, s->node_buf,
95                          2 * frontier * sizeof(*s->node_buf),  error);
96         FF_ALLOC_OR_GOTO(avctx, s->nodep_buf,
97                          2 * frontier * sizeof(*s->nodep_buf), error);
98         FF_ALLOC_OR_GOTO(avctx, s->trellis_hash,
99                          65536 * sizeof(*s->trellis_hash), error);
100     }
101 
102     avctx->bits_per_coded_sample = av_get_bits_per_sample(avctx->codec->id);
103 
104     switch (avctx->codec->id) {
105     case AV_CODEC_ID_ADPCM_IMA_WAV:
106         /* each 16 bits sample gives one nibble
107            and we have 4 bytes per channel overhead */
108         avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 /
109                             (4 * avctx->channels) + 1;
110         /* seems frame_size isn't taken into account...
111            have to buffer the samples :-( */
112         avctx->block_align = BLKSIZE;
113         avctx->bits_per_coded_sample = 4;
114         break;
115     case AV_CODEC_ID_ADPCM_IMA_QT:
116         avctx->frame_size  = 64;
117         avctx->block_align = 34 * avctx->channels;
118         break;
119     case AV_CODEC_ID_ADPCM_MS:
120         /* each 16 bits sample gives one nibble
121            and we have 7 bytes per channel overhead */
122         avctx->frame_size = (BLKSIZE - 7 * avctx->channels) * 2 / avctx->channels + 2;
123         avctx->bits_per_coded_sample = 4;
124         avctx->block_align    = BLKSIZE;
125         if (!(avctx->extradata = av_malloc(32 + AV_INPUT_BUFFER_PADDING_SIZE)))
126             goto error;
127         avctx->extradata_size = 32;
128         extradata = avctx->extradata;
129         bytestream_put_le16(&extradata, avctx->frame_size);
130         bytestream_put_le16(&extradata, 7); /* wNumCoef */
131         for (i = 0; i < 7; i++) {
132             bytestream_put_le16(&extradata, ff_adpcm_AdaptCoeff1[i] * 4);
133             bytestream_put_le16(&extradata, ff_adpcm_AdaptCoeff2[i] * 4);
134         }
135         break;
136     case AV_CODEC_ID_ADPCM_YAMAHA:
137         avctx->frame_size  = BLKSIZE * 2 / avctx->channels;
138         avctx->block_align = BLKSIZE;
139         break;
140     case AV_CODEC_ID_ADPCM_SWF:
141         if (avctx->sample_rate != 11025 &&
142             avctx->sample_rate != 22050 &&
143             avctx->sample_rate != 44100) {
144             av_log(avctx, AV_LOG_ERROR, "Sample rate must be 11025, "
145                    "22050 or 44100\n");
146             ret = AVERROR(EINVAL);
147             goto error;
148         }
149         avctx->frame_size = 512 * (avctx->sample_rate / 11025);
150         break;
151     case AV_CODEC_ID_ADPCM_IMA_SSI:
152         avctx->frame_size = BLKSIZE * 2 / avctx->channels;
153         avctx->block_align = BLKSIZE;
154         break;
155     default:
156         ret = AVERROR(EINVAL);
157         goto error;
158     }
159 
160     return 0;
161 error:
162     return ret;
163 }
164 
adpcm_encode_close(AVCodecContext * avctx)165 static av_cold int adpcm_encode_close(AVCodecContext *avctx)
166 {
167     ADPCMEncodeContext *s = avctx->priv_data;
168     av_freep(&s->paths);
169     av_freep(&s->node_buf);
170     av_freep(&s->nodep_buf);
171     av_freep(&s->trellis_hash);
172 
173     return 0;
174 }
175 
176 
adpcm_ima_compress_sample(ADPCMChannelStatus * c,int16_t sample)177 static inline uint8_t adpcm_ima_compress_sample(ADPCMChannelStatus *c,
178                                                 int16_t sample)
179 {
180     int delta  = sample - c->prev_sample;
181     int nibble = FFMIN(7, abs(delta) * 4 /
182                        ff_adpcm_step_table[c->step_index]) + (delta < 0) * 8;
183     c->prev_sample += ((ff_adpcm_step_table[c->step_index] *
184                         ff_adpcm_yamaha_difflookup[nibble]) / 8);
185     c->prev_sample = av_clip_int16(c->prev_sample);
186     c->step_index  = av_clip(c->step_index + ff_adpcm_index_table[nibble], 0, 88);
187     return nibble;
188 }
189 
adpcm_ima_qt_compress_sample(ADPCMChannelStatus * c,int16_t sample)190 static inline uint8_t adpcm_ima_qt_compress_sample(ADPCMChannelStatus *c,
191                                                    int16_t sample)
192 {
193     int delta  = sample - c->prev_sample;
194     int diff, step = ff_adpcm_step_table[c->step_index];
195     int nibble = 8*(delta < 0);
196 
197     delta= abs(delta);
198     diff = delta + (step >> 3);
199 
200     if (delta >= step) {
201         nibble |= 4;
202         delta  -= step;
203     }
204     step >>= 1;
205     if (delta >= step) {
206         nibble |= 2;
207         delta  -= step;
208     }
209     step >>= 1;
210     if (delta >= step) {
211         nibble |= 1;
212         delta  -= step;
213     }
214     diff -= delta;
215 
216     if (nibble & 8)
217         c->prev_sample -= diff;
218     else
219         c->prev_sample += diff;
220 
221     c->prev_sample = av_clip_int16(c->prev_sample);
222     c->step_index  = av_clip(c->step_index + ff_adpcm_index_table[nibble], 0, 88);
223 
224     return nibble;
225 }
226 
adpcm_ms_compress_sample(ADPCMChannelStatus * c,int16_t sample)227 static inline uint8_t adpcm_ms_compress_sample(ADPCMChannelStatus *c,
228                                                int16_t sample)
229 {
230     int predictor, nibble, bias;
231 
232     predictor = (((c->sample1) * (c->coeff1)) +
233                 (( c->sample2) * (c->coeff2))) / 64;
234 
235     nibble = sample - predictor;
236     if (nibble >= 0)
237         bias =  c->idelta / 2;
238     else
239         bias = -c->idelta / 2;
240 
241     nibble = (nibble + bias) / c->idelta;
242     nibble = av_clip_intp2(nibble, 3) & 0x0F;
243 
244     predictor += ((nibble & 0x08) ? (nibble - 0x10) : nibble) * c->idelta;
245 
246     c->sample2 = c->sample1;
247     c->sample1 = av_clip_int16(predictor);
248 
249     c->idelta = (ff_adpcm_AdaptationTable[nibble] * c->idelta) >> 8;
250     if (c->idelta < 16)
251         c->idelta = 16;
252 
253     return nibble;
254 }
255 
adpcm_yamaha_compress_sample(ADPCMChannelStatus * c,int16_t sample)256 static inline uint8_t adpcm_yamaha_compress_sample(ADPCMChannelStatus *c,
257                                                    int16_t sample)
258 {
259     int nibble, delta;
260 
261     if (!c->step) {
262         c->predictor = 0;
263         c->step      = 127;
264     }
265 
266     delta = sample - c->predictor;
267 
268     nibble = FFMIN(7, abs(delta) * 4 / c->step) + (delta < 0) * 8;
269 
270     c->predictor += ((c->step * ff_adpcm_yamaha_difflookup[nibble]) / 8);
271     c->predictor = av_clip_int16(c->predictor);
272     c->step = (c->step * ff_adpcm_yamaha_indexscale[nibble]) >> 8;
273     c->step = av_clip(c->step, 127, 24576);
274 
275     return nibble;
276 }
277 
adpcm_compress_trellis(AVCodecContext * avctx,const int16_t * samples,uint8_t * dst,ADPCMChannelStatus * c,int n,int stride)278 static void adpcm_compress_trellis(AVCodecContext *avctx,
279                                    const int16_t *samples, uint8_t *dst,
280                                    ADPCMChannelStatus *c, int n, int stride)
281 {
282     //FIXME 6% faster if frontier is a compile-time constant
283     ADPCMEncodeContext *s = avctx->priv_data;
284     const int frontier = 1 << avctx->trellis;
285     const int version  = avctx->codec->id;
286     TrellisPath *paths       = s->paths, *p;
287     TrellisNode *node_buf    = s->node_buf;
288     TrellisNode **nodep_buf  = s->nodep_buf;
289     TrellisNode **nodes      = nodep_buf; // nodes[] is always sorted by .ssd
290     TrellisNode **nodes_next = nodep_buf + frontier;
291     int pathn = 0, froze = -1, i, j, k, generation = 0;
292     uint8_t *hash = s->trellis_hash;
293     memset(hash, 0xff, 65536 * sizeof(*hash));
294 
295     memset(nodep_buf, 0, 2 * frontier * sizeof(*nodep_buf));
296     nodes[0]          = node_buf + frontier;
297     nodes[0]->ssd     = 0;
298     nodes[0]->path    = 0;
299     nodes[0]->step    = c->step_index;
300     nodes[0]->sample1 = c->sample1;
301     nodes[0]->sample2 = c->sample2;
302     if (version == AV_CODEC_ID_ADPCM_IMA_WAV ||
303         version == AV_CODEC_ID_ADPCM_IMA_QT  ||
304         version == AV_CODEC_ID_ADPCM_SWF)
305         nodes[0]->sample1 = c->prev_sample;
306     if (version == AV_CODEC_ID_ADPCM_MS)
307         nodes[0]->step = c->idelta;
308     if (version == AV_CODEC_ID_ADPCM_YAMAHA) {
309         if (c->step == 0) {
310             nodes[0]->step    = 127;
311             nodes[0]->sample1 = 0;
312         } else {
313             nodes[0]->step    = c->step;
314             nodes[0]->sample1 = c->predictor;
315         }
316     }
317 
318     for (i = 0; i < n; i++) {
319         TrellisNode *t = node_buf + frontier*(i&1);
320         TrellisNode **u;
321         int sample   = samples[i * stride];
322         int heap_pos = 0;
323         memset(nodes_next, 0, frontier * sizeof(TrellisNode*));
324         for (j = 0; j < frontier && nodes[j]; j++) {
325             // higher j have higher ssd already, so they're likely
326             // to yield a suboptimal next sample too
327             const int range = (j < frontier / 2) ? 1 : 0;
328             const int step  = nodes[j]->step;
329             int nidx;
330             if (version == AV_CODEC_ID_ADPCM_MS) {
331                 const int predictor = ((nodes[j]->sample1 * c->coeff1) +
332                                        (nodes[j]->sample2 * c->coeff2)) / 64;
333                 const int div  = (sample - predictor) / step;
334                 const int nmin = av_clip(div-range, -8, 6);
335                 const int nmax = av_clip(div+range, -7, 7);
336                 for (nidx = nmin; nidx <= nmax; nidx++) {
337                     const int nibble = nidx & 0xf;
338                     int dec_sample   = predictor + nidx * step;
339 #define STORE_NODE(NAME, STEP_INDEX)\
340                     int d;\
341                     uint32_t ssd;\
342                     int pos;\
343                     TrellisNode *u;\
344                     uint8_t *h;\
345                     dec_sample = av_clip_int16(dec_sample);\
346                     d = sample - dec_sample;\
347                     ssd = nodes[j]->ssd + d*(unsigned)d;\
348                     /* Check for wraparound, skip such samples completely. \
349                      * Note, changing ssd to a 64 bit variable would be \
350                      * simpler, avoiding this check, but it's slower on \
351                      * x86 32 bit at the moment. */\
352                     if (ssd < nodes[j]->ssd)\
353                         goto next_##NAME;\
354                     /* Collapse any two states with the same previous sample value. \
355                      * One could also distinguish states by step and by 2nd to last
356                      * sample, but the effects of that are negligible.
357                      * Since nodes in the previous generation are iterated
358                      * through a heap, they're roughly ordered from better to
359                      * worse, but not strictly ordered. Therefore, an earlier
360                      * node with the same sample value is better in most cases
361                      * (and thus the current is skipped), but not strictly
362                      * in all cases. Only skipping samples where ssd >=
363                      * ssd of the earlier node with the same sample gives
364                      * slightly worse quality, though, for some reason. */ \
365                     h = &hash[(uint16_t) dec_sample];\
366                     if (*h == generation)\
367                         goto next_##NAME;\
368                     if (heap_pos < frontier) {\
369                         pos = heap_pos++;\
370                     } else {\
371                         /* Try to replace one of the leaf nodes with the new \
372                          * one, but try a different slot each time. */\
373                         pos = (frontier >> 1) +\
374                               (heap_pos & ((frontier >> 1) - 1));\
375                         if (ssd > nodes_next[pos]->ssd)\
376                             goto next_##NAME;\
377                         heap_pos++;\
378                     }\
379                     *h = generation;\
380                     u  = nodes_next[pos];\
381                     if (!u) {\
382                         av_assert1(pathn < FREEZE_INTERVAL << avctx->trellis);\
383                         u = t++;\
384                         nodes_next[pos] = u;\
385                         u->path = pathn++;\
386                     }\
387                     u->ssd  = ssd;\
388                     u->step = STEP_INDEX;\
389                     u->sample2 = nodes[j]->sample1;\
390                     u->sample1 = dec_sample;\
391                     paths[u->path].nibble = nibble;\
392                     paths[u->path].prev   = nodes[j]->path;\
393                     /* Sift the newly inserted node up in the heap to \
394                      * restore the heap property. */\
395                     while (pos > 0) {\
396                         int parent = (pos - 1) >> 1;\
397                         if (nodes_next[parent]->ssd <= ssd)\
398                             break;\
399                         FFSWAP(TrellisNode*, nodes_next[parent], nodes_next[pos]);\
400                         pos = parent;\
401                     }\
402                     next_##NAME:;
403                     STORE_NODE(ms, FFMAX(16,
404                                (ff_adpcm_AdaptationTable[nibble] * step) >> 8));
405                 }
406             } else if (version == AV_CODEC_ID_ADPCM_IMA_WAV ||
407                        version == AV_CODEC_ID_ADPCM_IMA_QT  ||
408                        version == AV_CODEC_ID_ADPCM_SWF) {
409 #define LOOP_NODES(NAME, STEP_TABLE, STEP_INDEX)\
410                 const int predictor = nodes[j]->sample1;\
411                 const int div = (sample - predictor) * 4 / STEP_TABLE;\
412                 int nmin = av_clip(div - range, -7, 6);\
413                 int nmax = av_clip(div + range, -6, 7);\
414                 if (nmin <= 0)\
415                     nmin--; /* distinguish -0 from +0 */\
416                 if (nmax < 0)\
417                     nmax--;\
418                 for (nidx = nmin; nidx <= nmax; nidx++) {\
419                     const int nibble = nidx < 0 ? 7 - nidx : nidx;\
420                     int dec_sample = predictor +\
421                                     (STEP_TABLE *\
422                                      ff_adpcm_yamaha_difflookup[nibble]) / 8;\
423                     STORE_NODE(NAME, STEP_INDEX);\
424                 }
425                 LOOP_NODES(ima, ff_adpcm_step_table[step],
426                            av_clip(step + ff_adpcm_index_table[nibble], 0, 88));
427             } else { //AV_CODEC_ID_ADPCM_YAMAHA
428                 LOOP_NODES(yamaha, step,
429                            av_clip((step * ff_adpcm_yamaha_indexscale[nibble]) >> 8,
430                                    127, 24576));
431 #undef LOOP_NODES
432 #undef STORE_NODE
433             }
434         }
435 
436         u = nodes;
437         nodes = nodes_next;
438         nodes_next = u;
439 
440         generation++;
441         if (generation == 255) {
442             memset(hash, 0xff, 65536 * sizeof(*hash));
443             generation = 0;
444         }
445 
446         // prevent overflow
447         if (nodes[0]->ssd > (1 << 28)) {
448             for (j = 1; j < frontier && nodes[j]; j++)
449                 nodes[j]->ssd -= nodes[0]->ssd;
450             nodes[0]->ssd = 0;
451         }
452 
453         // merge old paths to save memory
454         if (i == froze + FREEZE_INTERVAL) {
455             p = &paths[nodes[0]->path];
456             for (k = i; k > froze; k--) {
457                 dst[k] = p->nibble;
458                 p = &paths[p->prev];
459             }
460             froze = i;
461             pathn = 0;
462             // other nodes might use paths that don't coincide with the frozen one.
463             // checking which nodes do so is too slow, so just kill them all.
464             // this also slightly improves quality, but I don't know why.
465             memset(nodes + 1, 0, (frontier - 1) * sizeof(TrellisNode*));
466         }
467     }
468 
469     p = &paths[nodes[0]->path];
470     for (i = n - 1; i > froze; i--) {
471         dst[i] = p->nibble;
472         p = &paths[p->prev];
473     }
474 
475     c->predictor  = nodes[0]->sample1;
476     c->sample1    = nodes[0]->sample1;
477     c->sample2    = nodes[0]->sample2;
478     c->step_index = nodes[0]->step;
479     c->step       = nodes[0]->step;
480     c->idelta     = nodes[0]->step;
481 }
482 
adpcm_encode_frame(AVCodecContext * avctx,AVPacket * avpkt,const AVFrame * frame,int * got_packet_ptr)483 static int adpcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
484                               const AVFrame *frame, int *got_packet_ptr)
485 {
486     int n, i, ch, st, pkt_size, ret;
487     const int16_t *samples;
488     int16_t **samples_p;
489     uint8_t *dst;
490     ADPCMEncodeContext *c = avctx->priv_data;
491     uint8_t *buf;
492 
493     samples = (const int16_t *)frame->data[0];
494     samples_p = (int16_t **)frame->extended_data;
495     st = avctx->channels == 2;
496 
497     if (avctx->codec_id == AV_CODEC_ID_ADPCM_SWF)
498         pkt_size = (2 + avctx->channels * (22 + 4 * (frame->nb_samples - 1)) + 7) / 8;
499     else if (avctx->codec_id == AV_CODEC_ID_ADPCM_IMA_SSI)
500         pkt_size = (frame->nb_samples * avctx->channels) / 2;
501     else
502         pkt_size = avctx->block_align;
503     if ((ret = ff_alloc_packet2(avctx, avpkt, pkt_size, 0)) < 0)
504         return ret;
505     dst = avpkt->data;
506 
507     switch(avctx->codec->id) {
508     case AV_CODEC_ID_ADPCM_IMA_WAV:
509     {
510         int blocks, j;
511 
512         blocks = (frame->nb_samples - 1) / 8;
513 
514         for (ch = 0; ch < avctx->channels; ch++) {
515             ADPCMChannelStatus *status = &c->status[ch];
516             status->prev_sample = samples_p[ch][0];
517             /* status->step_index = 0;
518                XXX: not sure how to init the state machine */
519             bytestream_put_le16(&dst, status->prev_sample);
520             *dst++ = status->step_index;
521             *dst++ = 0; /* unknown */
522         }
523 
524         /* stereo: 4 bytes (8 samples) for left, 4 bytes for right */
525         if (avctx->trellis > 0) {
526             FF_ALLOC_ARRAY_OR_GOTO(avctx, buf, avctx->channels, blocks * 8, error);
527             for (ch = 0; ch < avctx->channels; ch++) {
528                 adpcm_compress_trellis(avctx, &samples_p[ch][1],
529                                        buf + ch * blocks * 8, &c->status[ch],
530                                        blocks * 8, 1);
531             }
532             for (i = 0; i < blocks; i++) {
533                 for (ch = 0; ch < avctx->channels; ch++) {
534                     uint8_t *buf1 = buf + ch * blocks * 8 + i * 8;
535                     for (j = 0; j < 8; j += 2)
536                         *dst++ = buf1[j] | (buf1[j + 1] << 4);
537                 }
538             }
539             av_free(buf);
540         } else {
541             for (i = 0; i < blocks; i++) {
542                 for (ch = 0; ch < avctx->channels; ch++) {
543                     ADPCMChannelStatus *status = &c->status[ch];
544                     const int16_t *smp = &samples_p[ch][1 + i * 8];
545                     for (j = 0; j < 8; j += 2) {
546                         uint8_t v = adpcm_ima_compress_sample(status, smp[j    ]);
547                         v        |= adpcm_ima_compress_sample(status, smp[j + 1]) << 4;
548                         *dst++ = v;
549                     }
550                 }
551             }
552         }
553         break;
554     }
555     case AV_CODEC_ID_ADPCM_IMA_QT:
556     {
557         PutBitContext pb;
558         init_put_bits(&pb, dst, pkt_size);
559 
560         for (ch = 0; ch < avctx->channels; ch++) {
561             ADPCMChannelStatus *status = &c->status[ch];
562             put_bits(&pb, 9, (status->prev_sample & 0xFFFF) >> 7);
563             put_bits(&pb, 7,  status->step_index);
564             if (avctx->trellis > 0) {
565                 uint8_t buf[64];
566                 adpcm_compress_trellis(avctx, &samples_p[ch][0], buf, status,
567                                        64, 1);
568                 for (i = 0; i < 64; i++)
569                     put_bits(&pb, 4, buf[i ^ 1]);
570                 status->prev_sample = status->predictor;
571             } else {
572                 for (i = 0; i < 64; i += 2) {
573                     int t1, t2;
574                     t1 = adpcm_ima_qt_compress_sample(status, samples_p[ch][i    ]);
575                     t2 = adpcm_ima_qt_compress_sample(status, samples_p[ch][i + 1]);
576                     put_bits(&pb, 4, t2);
577                     put_bits(&pb, 4, t1);
578                 }
579             }
580         }
581 
582         flush_put_bits(&pb);
583         break;
584     }
585     case AV_CODEC_ID_ADPCM_IMA_SSI:
586     {
587         PutBitContext pb;
588         init_put_bits(&pb, dst, pkt_size);
589 
590         av_assert0(avctx->trellis == 0);
591 
592         for (i = 0; i < frame->nb_samples; i++) {
593             for (ch = 0; ch < avctx->channels; ch++) {
594                 put_bits(&pb, 4, adpcm_ima_qt_compress_sample(c->status + ch, *samples++));
595             }
596         }
597 
598         flush_put_bits(&pb);
599         break;
600     }
601     case AV_CODEC_ID_ADPCM_SWF:
602     {
603         PutBitContext pb;
604         init_put_bits(&pb, dst, pkt_size);
605 
606         n = frame->nb_samples - 1;
607 
608         // store AdpcmCodeSize
609         put_bits(&pb, 2, 2);    // set 4-bit flash adpcm format
610 
611         // init the encoder state
612         for (i = 0; i < avctx->channels; i++) {
613             // clip step so it fits 6 bits
614             c->status[i].step_index = av_clip_uintp2(c->status[i].step_index, 6);
615             put_sbits(&pb, 16, samples[i]);
616             put_bits(&pb, 6, c->status[i].step_index);
617             c->status[i].prev_sample = samples[i];
618         }
619 
620         if (avctx->trellis > 0) {
621             FF_ALLOC_OR_GOTO(avctx, buf, 2 * n, error);
622             adpcm_compress_trellis(avctx, samples + avctx->channels, buf,
623                                    &c->status[0], n, avctx->channels);
624             if (avctx->channels == 2)
625                 adpcm_compress_trellis(avctx, samples + avctx->channels + 1,
626                                        buf + n, &c->status[1], n,
627                                        avctx->channels);
628             for (i = 0; i < n; i++) {
629                 put_bits(&pb, 4, buf[i]);
630                 if (avctx->channels == 2)
631                     put_bits(&pb, 4, buf[n + i]);
632             }
633             av_free(buf);
634         } else {
635             for (i = 1; i < frame->nb_samples; i++) {
636                 put_bits(&pb, 4, adpcm_ima_compress_sample(&c->status[0],
637                          samples[avctx->channels * i]));
638                 if (avctx->channels == 2)
639                     put_bits(&pb, 4, adpcm_ima_compress_sample(&c->status[1],
640                              samples[2 * i + 1]));
641             }
642         }
643         flush_put_bits(&pb);
644         break;
645     }
646     case AV_CODEC_ID_ADPCM_MS:
647         for (i = 0; i < avctx->channels; i++) {
648             int predictor = 0;
649             *dst++ = predictor;
650             c->status[i].coeff1 = ff_adpcm_AdaptCoeff1[predictor];
651             c->status[i].coeff2 = ff_adpcm_AdaptCoeff2[predictor];
652         }
653         for (i = 0; i < avctx->channels; i++) {
654             if (c->status[i].idelta < 16)
655                 c->status[i].idelta = 16;
656             bytestream_put_le16(&dst, c->status[i].idelta);
657         }
658         for (i = 0; i < avctx->channels; i++)
659             c->status[i].sample2= *samples++;
660         for (i = 0; i < avctx->channels; i++) {
661             c->status[i].sample1 = *samples++;
662             bytestream_put_le16(&dst, c->status[i].sample1);
663         }
664         for (i = 0; i < avctx->channels; i++)
665             bytestream_put_le16(&dst, c->status[i].sample2);
666 
667         if (avctx->trellis > 0) {
668             n = avctx->block_align - 7 * avctx->channels;
669             FF_ALLOC_OR_GOTO(avctx, buf, 2 * n, error);
670             if (avctx->channels == 1) {
671                 adpcm_compress_trellis(avctx, samples, buf, &c->status[0], n,
672                                        avctx->channels);
673                 for (i = 0; i < n; i += 2)
674                     *dst++ = (buf[i] << 4) | buf[i + 1];
675             } else {
676                 adpcm_compress_trellis(avctx, samples,     buf,
677                                        &c->status[0], n, avctx->channels);
678                 adpcm_compress_trellis(avctx, samples + 1, buf + n,
679                                        &c->status[1], n, avctx->channels);
680                 for (i = 0; i < n; i++)
681                     *dst++ = (buf[i] << 4) | buf[n + i];
682             }
683             av_free(buf);
684         } else {
685             for (i = 7 * avctx->channels; i < avctx->block_align; i++) {
686                 int nibble;
687                 nibble  = adpcm_ms_compress_sample(&c->status[ 0], *samples++) << 4;
688                 nibble |= adpcm_ms_compress_sample(&c->status[st], *samples++);
689                 *dst++  = nibble;
690             }
691         }
692         break;
693     case AV_CODEC_ID_ADPCM_YAMAHA:
694         n = frame->nb_samples / 2;
695         if (avctx->trellis > 0) {
696             FF_ALLOC_OR_GOTO(avctx, buf, 2 * n * 2, error);
697             n *= 2;
698             if (avctx->channels == 1) {
699                 adpcm_compress_trellis(avctx, samples, buf, &c->status[0], n,
700                                        avctx->channels);
701                 for (i = 0; i < n; i += 2)
702                     *dst++ = buf[i] | (buf[i + 1] << 4);
703             } else {
704                 adpcm_compress_trellis(avctx, samples,     buf,
705                                        &c->status[0], n, avctx->channels);
706                 adpcm_compress_trellis(avctx, samples + 1, buf + n,
707                                        &c->status[1], n, avctx->channels);
708                 for (i = 0; i < n; i++)
709                     *dst++ = buf[i] | (buf[n + i] << 4);
710             }
711             av_free(buf);
712         } else
713             for (n *= avctx->channels; n > 0; n--) {
714                 int nibble;
715                 nibble  = adpcm_yamaha_compress_sample(&c->status[ 0], *samples++);
716                 nibble |= adpcm_yamaha_compress_sample(&c->status[st], *samples++) << 4;
717                 *dst++  = nibble;
718             }
719         break;
720     default:
721         return AVERROR(EINVAL);
722     }
723 
724     avpkt->size = pkt_size;
725     *got_packet_ptr = 1;
726     return 0;
727 error:
728     return AVERROR(ENOMEM);
729 }
730 
731 static const enum AVSampleFormat sample_fmts[] = {
732     AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE
733 };
734 
735 static const enum AVSampleFormat sample_fmts_p[] = {
736     AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_NONE
737 };
738 
739 #define ADPCM_ENCODER(id_, name_, sample_fmts_, capabilities_, long_name_) \
740 AVCodec ff_ ## name_ ## _encoder = {                                       \
741     .name           = #name_,                                              \
742     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),                    \
743     .type           = AVMEDIA_TYPE_AUDIO,                                  \
744     .id             = id_,                                                 \
745     .priv_data_size = sizeof(ADPCMEncodeContext),                          \
746     .init           = adpcm_encode_init,                                   \
747     .encode2        = adpcm_encode_frame,                                  \
748     .close          = adpcm_encode_close,                                  \
749     .sample_fmts    = sample_fmts_,                                        \
750     .capabilities   = capabilities_,                                       \
751     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,                           \
752 }
753 
754 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_IMA_QT,  adpcm_ima_qt,  sample_fmts_p, 0,                             "ADPCM IMA QuickTime");
755 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_IMA_SSI, adpcm_ima_ssi, sample_fmts,   AV_CODEC_CAP_SMALL_LAST_FRAME, "ADPCM IMA Simon & Schuster Interactive");
756 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav, sample_fmts_p, 0,                             "ADPCM IMA WAV");
757 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_MS,      adpcm_ms,      sample_fmts,   0,                             "ADPCM Microsoft");
758 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_SWF,     adpcm_swf,     sample_fmts,   0,                             "ADPCM Shockwave Flash");
759 ADPCM_ENCODER(AV_CODEC_ID_ADPCM_YAMAHA,  adpcm_yamaha,  sample_fmts,   0,                             "ADPCM Yamaha");
760